Virtual Reference Shelf

• NASA
• National Agricultual Library
• Jet Propulsion Laboratory
• Centers for Disease Control and Prevention
• Smithsonian Institution
• American Museum of Natural History
• Field Museum of Natural History, Chicago
• World Health Organization
• National Labs (DOE)
• National Library of Medicine
• Woods Hole Oceanographic Institution
• Marine Biological Laboratory
• Cold Spring Harbor Laboratory
• Scripps Institution of Oceanography
• National Severe Storms Laboratory

Directories

• Google Directory of Top Science Institutions
• Dmoz Directory of Science Institutions